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This article proposes a thrust equation model of two-degree-of-freedom oscillatory actuator considering its edge effect. The proposed thrust equation model clarifies that asymmetric permanent magnet flux linkage and inductance characteristics cause undesirable magnetic thrust and reluctance thrust, respectively.

In this paper, we propose a magnetic spring model utilizing an intrinsic localized mode (ILM). The ILM is observed in a lattice model which consists of multiple point masses and interactions (mechanical springs). The proposed model utilizes nonlinear magnetic springs in order to realize an ILM. The magnetic spring characteristics of the proposed model are investigated using a coupled simulation of FEM analysis and Matlab/Simulink.

Mobile haptic devices are being studied extensively because they have great potential for use as information transfer devices. Amemiya et al. proposed a method for haptic feedback with a slider-crank mechanism that uses an asymmetrical drive. We have recently proposed a haptic device that uses a small two degree-of-freedom (2-DOF) oscillatory actuator. Using this actuator, we have investigated the relationship of the properties of the asymmetric acceleration to haptic perception by conducting experiments on volunteers. Then, by applying a genetic algorithm to the optimization method, we created an optimized asymmetric acceleration waveform. However it has a different oscillations in operating directions. In this report, we propose a new oscillatory actuator using stepper motor principle to realize uniform oscillations in different directions. We verify that the proposed actuator is able to generate an asymmetric acceleration waveform.

Linear resonant actuators (LRAs) have been used in a wide range of applications [1] because they can reciprocate in a comparatively short stroke in spite of their compact size and light weight.

Linear resonant actuators (LRAs) use mechanical resonance and operate at high efficiency. However, the amplitude of LRAs do not follow target value when large external loads are applied. As a solution, it is effective to utilize electrical resonance and generate high current. In this paper, we propose a driving method to use electrical resonance. The effectiveness of the proposed method is verified through finite element analysis.

Linear resonant actuators have been used in a wide range of applications because they utilize mechanical resonance and operate at high efficiency. However, the amplitude of LRAs severely decreases when external loads are applied. To solve this problem, we applied PID control to an LRA and the mover amplitude remained constant against an external load. When a large external load is applied with the target voltage of PID control high, however, input power reaches maximum and the amplitude does not follow the target value. As a solution, it is effective to utilize electrical resonance and generate large current. In this paper, we propose a driving theory to generate electrical resonance. The effectiveness of the proposed method is verified through dynamic analysis using 2D finite element method.

Linear resonant actuators (LRAs) have been used in a wide range of applications [1] because they can reciprocate in a comparatively short stroke in spite of their compact size and light weight. However, the amplitude of LRAs severely decreases when external loads are applied. With applications such as electric shaver or air compressors, the amplitude of the mover needs to be able to be arbitrary controlled regardless of how the external load changes.

Linear oscillatory actuators (LOAs) have been used in a wide range of applications because they have a lot of advantages: high efficiency, simple structure, easy control, etc. [1]. Small-sized LOAs have a large potential to be used as handheld haptic devices in the near future. Haptic devices that generate a force vector using asymmetric acceleration can create the illusion of a pulling sensation without needing a grounded structure [2]. However, these devices are not suitable for mobile applications because of their size. Furthermore it can only produce a one-DOF force, and also generates unnecessary torque due to the rotation of the connecting rod.